JP2003079059A - On vehicle battery pack control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an on vehicle battery pack control device which is small and light by expanding usable capacity range of the battery with a simple device structure, while preventing over charge/discharge. SOLUTION: Discharging is started for measurement of a full charge capacity on condition that the voltage of each cell is all within a range between the full charge voltage and the over charge one (time t7); the discharge is terminated if the voltage of any one of the cells reaches the over discharge voltage value (time t8); and an integrated current value in the meantime is assumed as the full charge capacity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an on-vehicle assembled battery control method and device.

[0002]

2. Description of the Related Art In a secondary battery for a hybrid electric vehicle (HEV), the current capacity is calculated by adding or subtracting the integrated current amount from the full charge capacity set at the time of shipment, and the ratio of the current capacity to the full charge capacity is calculated. That is, the SOC is calculated,
This SOC has a predetermined intermediate range (for example, 40 to 60%)
By controlling the charging / discharging so as to satisfy the above condition, the charging / discharging is generally controlled so that both power generation by the discharging and regenerative braking by the charging can always be favorably dealt with. In a fuel cell vehicle (FCV) as well, it is possible to use a secondary battery in order to mitigate the sudden change in the output of the fuel cell. In this case, the secondary battery is also preferably SOC controlled as in the HEV vehicle. That is clear. As these in-vehicle assembled batteries,
Hydrogen storage alloy batteries and lithium secondary batteries have been put into practical use or are being studied.

Since a lithium secondary battery is vulnerable to overcharge and overdischarge, it has been proposed to equalize the cell voltage and reduce the variation in SOC between cells when the lithium secondary battery is used as an assembled battery. ing. For example, Japanese Patent Laid-Open No. 7-336905 discloses that a cell bypass circuit is connected in parallel for each cell and each cell bypass circuit is individually opened / closed by the detected difference in cell voltage to reduce the voltage variation between cells. is suggesting. In addition, the assembled battery is divided into a plurality of cell groups each composed of a plurality of cells (hereinafter, also referred to as a module or a block), a cell group bypass circuit is connected in parallel for each cell group, and a difference between detected cell group voltages is detected. It is also known to open / close each cell group bypass circuit individually to reduce the voltage variation between cell groups. Furthermore, overcharge and overdischarge are judged for each cell in each cell group, and when these overcharge and overdischarge are detected, the charging / discharging current of the assembled battery is controlled to further overcharge or overdischarge. It is also known to prevent the progress.

[0004]

As described above, the HE
In charging / discharging control of an assembled battery for V or FCV, control is performed within a predetermined range of SOC based on a preset full charge capacity, but the actual full charge capacity of the battery is deteriorated with time due to its use. It gradually decreases from the actual measured value or the assumed value at the time of shipment. As a result, even if it is determined that overcharge or overdischarge has not yet been reached based on the above current integration result, the cell that is most likely to be overcharged or overdischarged is actually overcharged or overdischarged, which may damage the battery, etc. There is a possibility that the above problems may occur, or that the expected dischargeable capacity value or chargeable capacity value is significantly smaller than those that are actually possible.

In order to avoid this problem, conventionally, the upper and lower limits of the variable capacity range of the battery to be used are set as close to the center as possible so that overcharging or overcharging may occur even if the full charge capacity decreases due to deterioration over time. The discharge is made to be hard to occur.

[0006] However, since such a countermeasure causes a decrease in usable capacity of the battery, there is a drawback that the battery pack becomes large and heavy, and the cost and the fuel consumption deteriorate accordingly. It was

The present invention has been made in view of the above-mentioned problems, and an on-vehicle assembled battery control for preventing overcharging / discharging and realizing a reduction in size and weight by expanding the usable capacity range of a battery with a simple device configuration. The purpose is to provide a device.

[0008]

According to another aspect of the present invention, there is provided an on-vehicle assembled battery control device, comprising: a vehicle-mounted assembled battery control device; An in-vehicle assembled battery including a current integrating unit that calculates an integrated current amount obtained by integrating charge and discharge currents and a battery management unit that manages the battery state of the assembled battery by performing an operation based on the output signals of the detection means. In the control device, the battery management unit is a full charge arrival time point when the voltage of each cell has reached a predetermined full charge voltage, and at least one of the voltage of each cell before or after the full charge arrival time point. Detects when one reaches the predetermined empty charge voltage and reaches the empty charge,
The integrated current amount between the both time points is set as the full charge capacity.

That is, in the present invention, the integrated current between the voltage level at which all the cells reach full charge and the voltage level at which any one of the cells reaches the empty charge voltage is regarded as the full charge capacity. The practicable full charge capacity of can be obtained with a simple circuit and a simple process. The full-charge voltage level is set so that even if the last cell reaches the full-charge voltage level, the cell most likely to be overcharged does not reach the over-charge voltage level.

According to the present invention, while preventing overcharging and discharging,
It is possible to realize an in-vehicle assembled battery control device that realizes a reduction in size and weight by expanding the usable capacity range of a battery with a simple device configuration.

Further description will be given below.

In the conventional on-vehicle assembled battery control device, in order to know the remaining capacity accurately by integrating the current, the full charge capacity and the full charge voltage value (SOC 100% voltage value) or the empty charge voltage value (SOC 0% voltage value). ) And need to know. That is, the state of charge or SOC is obtained by subtracting the integrated current value from the full charge voltage value or the empty charge voltage value from the full charge capacity.

As described above, in the conventional on-vehicle assembled battery control device, since the value set in advance at the time of initial shipment is used as the full charge capacity, the calculated remaining capacity error is due to the deterioration of the battery capacity due to the charging and discharging of the secondary battery. By increasing the capacity margin in advance in anticipation of it, as described above, it is possible to avoid problems such as being unable to discharge the expected capacity due to this error, or to separately provide overdischarge protection means and overcharge protection means. There is no choice but to adopt a method such as adding a means for reducing and correcting the initially set full-charge capacity with a calculation formula that is stored in advance with parameters such as a battery usage time. However, none of such conventional techniques has been able to obtain a great effect in terms of the control of the on-vehicle assembled battery control device and the optimum use of the on-vehicle assembled battery in vehicle traveling.

The inventors of the present invention do not require the use of the secondary battery in the traveling mode in a vehicle in which traveling power is generated by the secondary battery, particularly in HEV and FCV, and the vehicle and the fuel cell alone generate vehicle traveling energy. Focused on what can be done. Based on this viewpoint, the full charge level (SOC100
%) And the empty charge level (SOC0%), the charge or discharge is forcibly performed while the vehicle is running, and the integrated current amount during that time is calculated, so that the accurate full charge capacity at the present time can be grasped. Therefore, it is possible to realize battery protection (suppression of overcharging and overdischarging) and an increase in usable battery capacity, as compared with the related art in which an accurate full charge capacity cannot be grasped.

Moreover, since the process of calculating the full charge capacity can be executed by using the current integrating function and the battery voltage detecting function of the existing on-vehicle assembled battery control device, there is almost no increase in the circuit or device scale and the utility is excellent. . For example, a conventional on-vehicle assembled battery control device has an overdischarge detection circuit and an overcharge detection circuit for protecting the battery from over-discharge and over-charge, so if a part of these circuits is used, The function of the full-charge capacity detection circuit of the invention can be easily simplified, an increase in circuit scale can be suppressed, and an increase in manufacturing cost can be suppressed.

The implementation of the present invention is not limited to the running of the vehicle. For example, in an HEV or FCV equipped with a secondary battery that is used in combination with an engine or a fuel cell, it is not necessary to share the secondary battery when starting traveling, so the vehicle is stopped before the full charge capacity measurement of the present invention is performed. You may. Further, thereafter, the capacity of the battery pack may be automatically returned to a suitable level by operating the HEV or FCV.

According to a second aspect of the present invention, there is provided an on-vehicle assembled battery control device, which integrates charging / discharging currents of the assembled battery and a voltage detection unit for detecting voltages of a large number of cells which are connected to each other in series to constitute an assembled battery for an automobile. And a battery management unit that manages the battery state of the assembled battery by performing a calculation based on the output signals of both detection means. High level determination means for determining that the charging level is a predetermined high level when at least one of the cell voltages is equal to or higher than a predetermined high voltage value, and at least one of the voltage of each cell is higher than the high voltage value. Low level determination means for determining that the charging level is a predetermined low level when the voltage is less than a low predetermined low voltage value, and all the voltages of the cells are between the high voltage value and the low voltage value. Prescribed full charge capacity When the charging level is equal to or higher than the intermediate high voltage value for determination, the charge level is determined to be a predetermined intermediate high level, or all the voltages of the cells are the intermediate high voltage value and the low voltage value. Intermediate level determination means for determining the charge level to be a predetermined intermediate low level when it becomes less than the intermediate low voltage value for determining a predetermined full charge capacity detection time point, and the charge level is equal to or higher than the intermediate high level. Until the low level or the intermediate low level is reached by starting the discharge from the time when the discharge starts below the high level, or
Full charge capacity based on the integrated current value obtained by performing current integration until the high level or the intermediate high level is reached by starting charging from the charging start point of the low level or higher at the intermediate low level or lower. It is characterized by a full charge capacity calculation means for calculating

That is, in this configuration, when the discharge (or the charge) for measuring the full charge capacity is started, whether the voltage variation between cells (related to the capacity variation) is converged within the allowable range. When it is converged, discharge (or charge) for measuring the full charge capacity is started.

As a result, it is possible to prevent an erroneous measurement of the full charge capacity which is smaller than the case where the above variation is eliminated by integrating the full charge capacity in a state where there is a large variation between the cells, and it is possible to accurately use the same. The full charge capacity can be measured.

In a preferred embodiment, each of the above-mentioned judging means is
It is composed of a comparator that compares each cell voltage with a reference voltage, and a logic circuit that outputs a signal corresponding to a logical sum output or a logical product output of the binary output voltages output from these comparators. As a result, it is not necessary to transmit the voltage values of a large number of cells to the microcomputer one by one, and the signal transmission circuit system can be simplified. Particularly, this advantage is particularly high in a high voltage assembled battery in which it is preferable to electrically insulate the power supply voltage of the microcomputer for controlling charge or discharge for the full charge capacity measurement from the assembled battery in which the potential of each cell is different. It is suitable.

According to a third aspect of the present invention, in the on-vehicle assembled battery control device according to the second aspect, the battery management section further includes a current bypass circuit connected in parallel with each of the cells and bypassing a current of the cell. And a cell voltage equalizing circuit having a bypass control circuit that controls the voltage variation between the cells within a predetermined range by adjusting the bypass current of the current bypass circuit according to the voltage variation between the cells. It is characterized by doing.

According to this structure, when the voltage variation (related to the capacity variation) between the cells is not converged within the allowable range by the configuration of claim 2, the discharge for measuring the full charge capacity ( (Or charging), then,
Since the cell voltage equalization circuit reduces the voltage variation among the cells, it is possible to restart the discharge (or charge) for measuring the full charge capacity after a predetermined time after the interruption.

That is, if the voltage variation between cells is small in the vicinity of full charge (empty charge), the discharge (charge) for measuring the full charge capacity is immediately executed, so that the full charge capacity can be quickly obtained. On the contrary, if the voltage variation between cells is large near full charge (empty charge), the discharge (charge) for full charge capacity measurement is executed after waiting for the variation reduction by the cell voltage equalization circuit. Accurate full-charge capacity measurement can be realized despite voltage variations between cells.

Further, in order to detect the full charge capacity, if the cell voltages are made to be, for example, between the full charge voltage (intermediate high voltage value) and the overcharge voltage (high voltage value), the first cell is charged to the full charge. It is also possible to prevent the cell that has reached full charge from falling into overcharge during the period from when the last cell reaches full charge until the last cell reaches full charge. Therefore, it is possible to easily arrange the voltage range within which the discharge (or charge) can be started.

According to a fourth aspect of the present invention, in the on-vehicle assembled battery control device according to the second or third aspect, the battery management unit sets the predetermined high voltage value, which is a determination reference value of the high level determination means, to the predetermined high voltage value. It is characterized in that the cell is set to the allowable upper limit voltage value of the cell, and when the high level determination means determines the high level, the reduction or interruption of the charging current is instructed.

That is, in the present configuration, "high level determination" by the high level determination means, that is, when any cell voltage becomes equal to or higher than the allowable upper limit voltage value, the charge current is reduced or cut off. To prevent all the cells that have reached the intermediate high voltage from exceeding the permissible upper limit voltage value when aligning all the cell voltages above the intermediate high voltage before the start of discharge for full charge capacity measurement. By further equalizing the cell voltage thereafter, the cell voltage can be made equal to or higher than the intermediate high voltage thereafter, and the discharge start for the full charge capacity measurement can be performed.

According to a fifth aspect of the present invention, in the on-vehicle assembled battery control device according to the second or third aspect, the battery management section sets the predetermined low voltage value, which is a determination reference value of the low level determination means, to the predetermined low voltage value. It is characterized in that the cell is set to the allowable lower limit voltage value of the cell, and when the low level determination means determines that the cell is at a low level, the discharge current is reduced or cut off.

That is, in this configuration, the "low level determination" by the low level determination means, that is, when any one of the cell voltages becomes less than the allowable lower limit voltage value, the discharge current reduction or interruption is instructed. When aligning all the cell voltages below the intermediate low voltage before the start of charging for full charge capacity measurement, the cells that first reached the intermediate low voltage will drop below the allowable lower limit voltage value. Further, the cell voltage can be equalized below the intermediate low voltage by the equalization of the cell voltage thereafter, and the discharge start for the full charge capacity measurement can be performed.

According to a sixth aspect of the present invention, in the on-vehicle assembled battery control device according to any of the second to fifth aspects, each of the cells includes a lithium secondary battery having a positive electrode and a negative electrode capable of inserting and extracting lithium ions. In each case, the high level determination means comprises overcharge detection means for detecting overcharge of each cell, and the low level determination means comprises overdischarge detection means for detecting overdischarge of each cell. It has a feature.

That is, according to this configuration, since the high level determination means and the low level determination means are constituted by the existing overcharge detection means and overdischarge detection means which are provided in the ordinary lithium assembled battery, In order to control the charging (or discharging) to a predetermined voltage for measuring the full charge capacity performed after the cell voltage is converged to a predetermined voltage range, the intermediate high level determination or the intermediate low level determination is performed. Only the circuit needs to be added, and the circuit configuration can be simplified. Furthermore, since the lithium assembled battery is usually equipped with the cell voltage equalizing circuit, it is possible to suppress an increase in the circuit scale particularly when carrying out claim 7.

According to a seventh aspect of the present invention, in the on-vehicle assembled battery control apparatus according to any of the second to sixth aspects, the high level determination means and the intermediate low level determination means are the voltage of each cell and a predetermined reference. And a plurality of comparison units for comparing the value for each cell, the logical sum operation unit for outputting a logical signal corresponding to the logical sum of the output of each comparison unit, and the reference value of each comparison unit, It is characterized by comprising a threshold value switching unit for switching between the first threshold value for high level determination and the second threshold value for intermediate low level determination.

In this configuration, by adding the threshold value switching unit, it is possible to realize the common use of the circuit between the high level judgment unit and the intermediate low level judgment unit, and it is possible to realize the simplification of the circuit. .

According to the eighth aspect of the present invention, in the on-vehicle assembled battery control apparatus according to any of the second to sixth aspects, the low level determination means and the intermediate high level determination means further include the voltage of each cell and a predetermined value. A plurality of comparison units that compare a reference value for each cell, and a logical product operation unit that outputs a logical signal corresponding to the logical product of the outputs of the comparison units; and the reference values of the comparison units. , And a threshold value switching unit for switching between the third threshold value for low level determination and the fourth threshold value for intermediate high level determination.

In this configuration, by adding the threshold value switching unit, it is possible to realize commonalization of the circuit between the low level determination means and the intermediate high level determination means, and to realize simplification of the circuit. .

According to a ninth aspect of the present invention, in the on-vehicle assembled battery control apparatus according to any one of the second to eighth aspects, the current for changing the output current amount output to a single output line by the output of each of the determination means is further provided. It is characterized by having a modulation means.

According to this structure, the number of output lines can be reduced.

According to a tenth aspect of the invention, there is provided the vehicle-mounted battery control device according to the seventh or eighth and ninth aspects.
A sampling switch that periodically samples the output current of the output line and outputs the sampled current to a signal processing circuit at a subsequent stage, and a threshold switch of the threshold switching unit based on a change in the output current of the current modulation unit due to opening and closing of the sampling switch. And a threshold switching signal generating means for instructing threshold switching.

According to this configuration, threshold switching can be performed without requiring a control signal from a subsequent signal processing unit such as a microcomputer that performs signal processing, and the circuit configuration can be simplified by saving the photo coupler. can do.

According to the eleventh aspect of the present invention, in the on-vehicle assembled battery control device according to any one of the second to fourth aspects or the sixth aspect, the battery management unit sets the state of each cell to the intermediate level when detecting the full charge capacity. A charge command operation for charging to a level below the high level above a level, a shutoff command operation for shutting off a charging current when one of the cells reaches the high voltage value, and after a predetermined time has elapsed from the shutoff, all When the cell is equal to or higher than the intermediate high voltage value and lower than the high voltage value, a discharge command operation for permitting discharge for current accumulation for full charge capacity acquisition thereafter is executed.

According to this control configuration, it is possible to prevent each cell from exceeding the above-mentioned high voltage value before the full-charge capacity is detected, and to induce so as to exceed all the intermediate high-voltage values. It is possible to reliably detect the full charge capacity by discharging for the full charge capacity. In particular, this structure can be implemented in a lithium battery pack while suppressing the addition of the circuit structure.

According to a twelfth aspect of the present invention, in the on-vehicle assembled battery control device according to the eleventh aspect, the battery management section further comprises:
When detecting the full charge capacity, a reduction command operation for reducing the charging current is executed every time the cell voltage reaches the high voltage value between the charging command operation and the cutoff command operation.

According to this control configuration, it is possible to induce each cell to exceed all the intermediate high voltage values while suppressing each cell from exceeding the high voltage value before the full charge capacity is detected. It is possible to reliably detect the full charge capacity by discharging for the full charge capacity.

The structure according to claim 13 is the same as claim 11 or
In the on-vehicle assembled battery control device according to 2, the battery management unit further detects a predetermined current when at least one cell drops below the intermediate high voltage value after a lapse of a predetermined time from the cutoff in detecting the full charge capacity. It is characterized by executing a recharge command operation for recharging at a value.

According to this control configuration, it is possible to induce each cell to exceed all the intermediate high voltage values while suppressing each cell from exceeding the high voltage value before the full charge capacity is detected. It is possible to reliably detect the full charge capacity by discharging for the full charge capacity.

According to the structure described in claim 14, in the on-vehicle assembled battery control device according to any one of claims 2 to 5, the assembled battery for a vehicle further stores electric power for assisting or regenerating the power of the hybrid electric vehicle. However, the battery management unit increases or decreases the discharge current or the charging current at the time of integrating the full charge capacity according to the required value of the output or the regenerative current of the hybrid electric vehicle during traveling so that the required value can be secured. Therefore, it is possible to prevent the discharge or charge at the time of full charge capacity integration from affecting the running of the vehicle.

[0046]

BEST MODE FOR CARRYING OUT THE INVENTION A HEV motor control device using an on-vehicle assembled battery control device of the present invention will be described in detail with reference to the following embodiments.

[0047]

First Embodiment (Overall Structure) FIG. 1 shows a block circuit diagram of this HEV motor control device.

In FIG. 1, the assembled battery 1 is divided into N cell groups 11 to 1N each having 4 cells as one cell group in order from the high voltage side, and the potential VS1 of each cell group 11 to 1N, VS2, VS3, VS4, VSn +
1 is detected by the battery controller 2 through the lines L1, L5, L9, ... Ln + 1.

In addition, the simple cell overcharge / discharge detection devices 31 to 31.
N is provided on a one-to-one basis for each cell group 11 to 1N, and the simple cell overcharge / discharge detection devices 31 to 3N have at least one or more overcharged or overdischarged cells in the cell group to which they belong. It is determined whether or not there is, and the result is transmitted to the battery controller 2, and the variation of the cell voltage in the cell group to which the cell controller 2 belongs is canceled.
Battery controller 2 and simple cell overcharge / discharge detection device 31-
The 3N constitutes the in-vehicle assembled battery control device according to the present invention.

The battery controller 2 calculates necessary assembled battery information (for example, SOC, overvoltage alarm, overcharge alarm, etc.) based on the charge / discharge current of the assembled battery 1 obtained from the current sensor 8 and the above information, and this assembly The battery information is output to the vehicle control device 5, the group voltage variations among the cell groups 11 to 1N are eliminated, and the full charge capacity of the assembled battery 1 is controlled.

The vehicle control device 5 controls the inverter 6 based on the assembled battery information obtained from the battery controller 2 and the current sensor 8 and vehicle traveling information (vehicle speed, engine torque, accelerator opening degree, etc.). The pair of DC input ends of the inverter 6 are individually controlled by the power supply line 9U and the ground line 9D to the positive and negative ends of the battery pack 1, and orthogonal bidirectional conversion between the battery pack 1 and the three-phase AC motor 7 is performed. Then, the driving of the three-phase AC motor 7 and the charging / discharging of the assembled battery 1 are controlled. (Simplified Cell Overcharge / Discharge Detection Devices 31 to 3N) Specific circuit configurations of the simplified cell overcharge / discharge detection device 31 shown in FIG. 1 are shown in FIGS. 2, 3, 5, and 6.

The simple cell overcharge / discharge detection devices 31 to 3N are
For each cell group, the overcharge detection circuit CCC (see Fig. 2) that detects overcharge of each cell, the overdischarge detection circuit CDC (see Fig. 3) that detects overdischarge of each cell, and the voltage variation between each cell Simple equalization circuit CEC for compensation (see Fig. 5), full charge detection circuit CFC for detecting full charge of each cell (see Fig. 6)
Built in.

Since the overcharge detection circuit CCC, the overdischarge detection circuit CDC, the simple equalization circuit CEC and the full charge detection circuit CFC of each of the simple cell overcharge / discharge detection devices 31 to 3N are the same, the simple cells of the cell group 11 are the same. Only those of the overcharge / discharge detection device 31 will be described below. (Overcharge detection circuit CCC) Simple cell overcharge / discharge detection device 31
The overcharge detection circuit CCC will be described with reference to FIG.

The overcharge detection circuit CCC includes four comparison unit circuits 311 each having the same circuit configuration and arranged for each cell, and a diode OR circuit for outputting the logical sum signal voltage of the output of each comparison unit circuit 311. 312, a NOT circuit 313 having a transistor TRO interrupted by the output voltage of the diode OR circuit 312, and a NOT circuit 31
3 and a signal current generation circuit 314 having a transistor TR2 which is intermittently connected by the output voltage of the third transistor.

Since each comparison unit circuit 31 has the same structure, only the comparison unit circuit 311 for detecting overcharge of the uppermost cell 10 will be described below.

The comparison unit circuit 311 includes a resistance voltage dividing circuit including resistors RUA and RUB connected in series with each other,
A reference voltage circuit including a resistor RUV and a reference voltage source VRU (for example, a Zener diode) connected in series with each other,
It is composed of an overcharge detection comparator C1 to which a voltage is input respectively.

The overcharge detection comparator C1 is provided in the cell 10
When the cell voltage, that is, the cell voltage exceeds the reference high voltage value output by the reference voltage circuit, a high level potential is output to the diode OR circuit 312.

Therefore, the diode OR circuit 312
Turns on the transistor TR0 when the cell voltage of any one of the four cells exceeds the reference high voltage value, and as a result, the transistor TR2 turns on.

The output line L of the simple cell overcharge / discharge detection device 31 is connected to the low input impedance input terminal OCD1 of the battery controller 2 and, as a result, the transistor
When TR2 is turned on, a signal current i2 that is substantially inversely proportional to the resistance value of the collector resistor R2 is sent to the input terminal OCD1. (Overdischarge detection circuit CDC) Simple cell overcharge / discharge detection device 31
The over-discharge detection circuit CDC will be described with reference to FIG.

The over-discharge detection circuit CDC has four comparison unit circuits 315 each having the same circuit configuration and arranged for each cell, and a transistor type of outputting the logical product signal voltage of the output of each comparison unit circuit 315. NAND circuit 316
And a signal current generation circuit 317 having a transistor TR1 which is intermittently connected by the output voltage of the NAND circuit 316.

Since each comparison unit circuit 315 has the same structure, only the comparison unit circuit 315 for detecting overcharge of the uppermost cell 10 will be described below.

The comparison unit circuit 315 includes a resistance voltage dividing circuit including resistors RLA and RLB connected in series with each other,
A reference voltage circuit including a resistor RLV and a reference voltage source VRL (for example, a Zener diode) connected in series with each other,
It is composed of an over-discharge detection comparator C2 to which a voltage is respectively input from them.

The overdischarge detection comparator C2 is provided in the cell 10
When the cell voltage, that is, the cell voltage exceeds the reference low voltage value output by the reference voltage circuit, a high level is output to one transistor TR of the NAND circuit 316.

Therefore, in the NAND circuit 316 in which the four transistors TR to which the outputs from the comparison unit circuits 315 are individually input are connected in series, all the cell voltages of the four cells exceed the reference low voltage value. In this case, the transistor TR1 is turned on. The signal current generation circuit 317 having the transistor TR1 is logically a NOT circuit, and in the end,
A signal current i1 corresponding to the logical product of the outputs of the comparison unit circuits 315 is output to the output line L of the simple cell overcharge / discharge detection device 31. That is, as described above, the output line L is connected to the low input impedance input terminal OCD1 of the battery controller 2, and as a result, when the transistor TR1 is turned on, the signal current that is approximately inversely proportional to the resistance value of the collector resistance R1 thereof. i1 is sent to the input terminal OCD1.

Further, a bias resistor R0 is connected between the line L1 and the output line L, and the bias resistor R0 supplies a constant bias current i0 to the output line L.

(Full Charge Detection Circuit CFC) The full charge detection circuit CFC of the simple cell overcharge / discharge detection device 31 will be described with reference to FIG.

The full-charge detection circuit CFC has four comparison unit circuits 318 each having the same circuit configuration and arranged for each cell, and a transistor type of a transistor for outputting the logical product signal voltage of the output of each comparison unit circuit 318. NAND circuit 319
And a signal current generating circuit 320 having a transistor TR3 which is intermittently connected by the output voltage of the NAND circuit 319.

Since each comparison unit circuit 318 has the same structure, only the comparison unit circuit 318 for detecting the full charge of the uppermost cell 10 will be described below.

The comparison unit circuit 318 includes a resistance voltage dividing circuit including resistors RFA and RFB connected in series with each other,
A reference voltage circuit composed of a resistor RUF and a reference voltage source VRF (for example, a Zener diode) connected in series with each other,
It is composed of a full-charge detection comparator C3 to which a voltage is input respectively.

The full charge detection comparator C3 is a cell 10
When the cell voltage, that is, the cell voltage exceeds the reference full charge voltage value (intermediate high voltage value) output by the reference voltage circuit, a high level is output to one transistor TR ′ of the NAND circuit 319.

Therefore, in the NAND circuit 319 in which the four transistors TR ′ to which the outputs from the respective comparison unit circuits 318 are individually input are connected in series, all the cell voltages of the four cells are equal to the reference full charge voltage value. When it exceeds, the transistor TR3 is turned on. The signal current generation circuit 320 having the transistor TR3 is a NOT circuit logically,
Eventually, the signal current i3 corresponding to the logical product of the outputs of the comparison unit circuits 318 is output to the output line L of the simple cell overcharge / discharge detection device 31. That is, as described above, the output line L is connected to the low input impedance input terminal OCD1 of the battery controller 2, and as a result,
When the transistor TR3 is turned on, a signal current i3 that is substantially inversely proportional to the resistance value of the collector resistor R3 is sent to the input terminal OCD1.

(Simple Equalization Circuit CEC) The simple equalization circuit CEC of the simple cell overcharge / discharge detection device 31 will be described with reference to FIG. The simple equalization circuit CEC is a circuit for eliminating variations in inter-cell voltage.

The group voltage V11 of the cell group 11 is input to a resistance voltage divider circuit in which four resistors R10 to R13 having the same resistance value are connected in series to input 25% potential, 50% potential,
A 75% potential is formed. 25% potential, 50% potential, 7
The 5% potential represents the potential of 25%, 50%, and 75% of the group voltage with reference to the lowest potential VS2 of the cell group 11.

The operational amplifier voltage amplifier circuits OP1 to OP3 have the potentials of three cell connection points of the cell group 11 and 25% of these potentials.
The potential difference (voltage variation) between the potential, 50% potential, and 75% potential is analog differentially amplified, and the output voltage indicating the amplified potential difference (voltage variation) is output to the comparators CP1H, CP1L,
Output to CP2H, CP2L, CP3H, CP3L.

The comparator CP1H determines whether the potential variation at the first cell connection point from the high potential side is larger than the predetermined reference variation width on the high voltage side. The comparator CP1L determines whether or not the potential variation at the first connection point from the high potential side is larger than the predetermined reference variation width on the low voltage side.

The comparator CP2H determines whether the potential variation at the second cell connection point from the high potential side is larger than the predetermined reference variation width on the high voltage side. Comparator CP21
L determines whether or not the potential variation at the second connection point is larger on the low voltage side than the predetermined reference variation width.

The comparator CP3H determines whether the potential variation at the third cell connection point from the high potential side is larger than the predetermined reference variation width on the high voltage side. Comparator CP3L
Determines whether the potential variation at the third connection point is larger on the low voltage side than the predetermined reference variation width.

These determination results are passed through the logic circuit 321 to the current bypass switches 322 to 322 for eliminating the cell variation.
To 325. As a result, if the cell voltage of the highest-potential cell 10 is higher than the average cell voltage by the allowable level or more, the cell bypass switch 322 is turned on, and as a result, the charging current that should flow into the highest-potential cell 10 at the time of charging. Is shunted to the bypass resistance RB1, and during discharge, the cell 10 having the highest potential performs additional bypass discharge to the bypass resistance RB1 to reduce the cell voltage of the cell 10 having the highest potential. Eventually, variations in cell voltage are reduced. The simple equalization circuit CEC using the logic circuit 321 is publicly known and is not the gist of the invention, and therefore a detailed description thereof will be omitted.

(Battery Controller 2) The battery controller 2 is shown in FIG. The battery controller 2 detects a current change in the output line L for each of the cell groups 11 to 1N, receives overcharge, overdischarge, and full charge, and calculates a variation between cell group voltages. Aim to reduce.

In order to simplify the illustration and description of the circuit description of the battery controller 2, circuit blocks other than the circuit blocks that perform overcharge, overdischarge, reception of full charge of the cell group 11 and current bypass of the cell group 11 will be described. The illustration is omitted. Reference numeral 100 is a microcomputer for arithmetic processing.

The battery state of the cell group 11 (whether overcharged, overdischarged, fully charged or not) is input to the voltage conversion circuit 21 through the output line L and the sampling switch 20 and converted into a voltage signal, and this voltage signal is multiplexed. Two
2 is input to the microcomputer 100. The group voltage V11 of the cell group 11 is converted into a digital voltage signal by the A / D converter 23, and then the multiplexer 24
Through the microcomputer 100. The multiplexers 22 and 24 sequentially select one of the same voltages as those obtained for each of the cell groups 11 to 1N in a time-sequential manner to select the microcomputer 1
Enter 00.

The microcomputer 100 includes the cell groups 11 to 11
The group voltage of 1N is compared, and the transistor 27, which is a group bypass switch, is turned on through the demultiplexer 25 and the photocoupler 26 in order to adjust all the group voltages to the minimum group voltage. Bypass discharge (or charge bypass) of cell groups other than the group voltage cell group
Then, each cell group voltage is converged within a predetermined range. (Measurement of Full Charge Capacity) The full charge capacity measurement operation performed by the microcomputer 100 and forming the essential part of this embodiment will be described below with reference to the flowchart shown in FIG. 7 and the timing chart shown in FIG. To simplify the description, the cell group 11 will be described. Other cell groups 12
The operation is the same for .about.1N.

When the battery controller 2 starts the full charge capacity measuring mode from the time t0, the battery pack 1 causes the main circuit current I to rise.
It is charged at c1 and the voltage of each cell gradually rises. Since all cell voltages normally exceed the overdischarge detection threshold value VL, only the transistor TR1 for overdischarge detection is turned on.
And the total current (that is, the transmission signal) Σ flowing from the output line L to the input terminal OCD1 of the battery controller 2
i becomes i0 + i1, and it is transmitted to the battery controller 2 that all cells are in the normal use range between the overdischarge voltage VL and the overcharge voltage VU.

At time t1, the cell voltage VCMAX of one of the cells having the highest voltage reaches the overcharge detection threshold VU and the transistor TR2 is turned on, so that the total current Σi
Increases by the current i2. The battery controller 2 detects this increase in the current i2 and controls the inverter 6 to reduce the charging current for charging the assembled battery 1 from IC1 to IC2. Due to this decrease in charging current, the cell voltage is reduced by the amount of decrease in internal voltage drop, so overcharge detection is temporarily canceled.
The total current Σi decreases by the current i2. However, the battery pack 1
Is still charged with the charging current Ic2, the voltage of each cell gradually rises.

At time t2, the cell voltage VCMAX of the cell having the highest voltage reaches the overcharge detection threshold VU again and the transistor TR2 is turned on, so that the total current Σi increases by the current i2. The battery controller 2 uses this current i
When the increase of 2 is detected, the inverter 6 is controlled to decrease the charging current for charging the assembled battery 1 from IC2 to IC3. Since the cell voltage decreases as described above due to the decrease in the charging current, the overcharge detection is temporarily canceled, and the total current Σi decreases by the current i2. However, since the assembled battery 1 is still charged with the charging current Ic2, the voltage gradually increases.

At time t3, the cell voltage VCMAX of the cell having the highest voltage reaches the overcharge detection threshold VU again and the transistor TR2 is turned on, so that the total current Σi increases by the current i2. The battery controller 2 uses this current i
When the increase of 2 is detected and the inverter 6 is controlled, the charging current for charging the assembled battery 1 is changed from IC3 to 0, and charging is performed for a predetermined time TW.
The cell voltage is stopped by 1, and the cell voltage equalization circuit CEC performs cell voltage equalization during this period to reduce variations in cell voltage.

The microcomputer 100 always (to be exact, periodically) determines whether the total current Σi = i0 + i1 + i3. This state indicates that each cell voltage is in the voltage range in which it is equal to or higher than the full charge voltage and does not reach the overcharge voltage. That is, this voltage range has a small voltage variation between the cell voltages, and in the subsequent discharge for measuring the full charge capacity, the full charge capacity is not underestimated due to this voltage variation. It shows that it is suitable for starting discharge for measuring the charge capacity.

When charging is restarted at time t4 when a predetermined time TW1 has elapsed from time t3, the cell voltage of the cell having the highest voltage does not reach the overcharge voltage and the voltage is the lowest at time t5. The cell voltage VCMIN of the cell becomes higher than a predetermined full charge voltage Vf. Then the transistor
TR3 is turned on and the current I3 is output, whereby the battery controller 2 recognizes that all the cells are at the full charge voltage or higher.

Thereafter, at time t6, the cell voltage VCMAX of the cell having the highest voltage reaches the overcharge detection threshold VU again, the current i2 temporarily flows as described above, and the microcomputer 100 charges. Stop. This state is the battery pack 1
Means that the capacity of is the largest in the allowable cell voltage range.

In this embodiment, the predetermined time TW2 is set between this charge stop and the next discharge start (time t7) for full charge capacity measurement. Even during this predetermined time TW2, the simple equalizing circuit CEC is operating, and each cell can be further converged at the full charge voltage VF or more and the overcharge voltage VU or less while further equalizing the cell voltage VC.

By waiting for the next discharge for the predetermined time TW2, it is confirmed that any cell will not drop below the full charge voltage Vf due to its own state failure during the waiting. Make sure that you can safely discharge for full charge capacity.

After the above confirmation, at time t7, discharging for measuring the full charge capacity is started. If any cell voltage VC falls below the full charge voltage Vf before the end of the predetermined period TW2, the assembled battery 1 is recharged with the charge current IC3.

When the discharge is started, the cell voltage gradually decreases, the minimum cell voltage VCMIN becomes less than the overdischarge threshold voltage VL at time t8, the transistor TR1 is turned off, and the total current Σi is only the current i0. Becomes The microcomputer 100 detects it, determines that it is in an over-discharged state, stops the discharge, detects the discharge current during this discharge (time t7 to time t8) by the current sensor 8, and integrates it to obtain the full charge capacity. To calculate.

[0094]

Second Embodiment Another embodiment will be described below with reference to FIGS. 9 and 10.

In this embodiment, the function of the overcharge detection circuit shown in FIG. 3 is combined with the full charge detection circuit shown in FIG. 6 in the first embodiment. Since the operation of the circuit in each cell is the same, only full-charge detection and over-discharge detection of the cell having the highest potential in the cell group 11 will be described below. (Full Charge / Over-Discharge Detection Circuit CXC) The full-charge / over-discharge detection circuit CXC will be described with reference to FIG.

This full charge / over discharge detection circuit CXC is shown in FIG.
In the full charge detection circuit CFC shown in (4), four threshold value switching circuits 400 for switching threshold values and a threshold value switching control circuit 401 for controlling each threshold value switching circuit 400 are added. The full-charge detection circuit CFC has already been described, so its explanation is omitted.

Since the threshold switching circuit 400 has the same circuit configuration and is arranged for each cell, only the threshold switching circuit 400 of the cell 10 having the highest potential will be described. The threshold value switching circuit 400 includes resistors R1 ', R2', R3 ', a diode D', a transistor TR connected in series with each other.
It consists of 41. The resistors R1 ′, R2 ′ and the diode D ′ are connected in series with each other, the transistor TR41 is interrupted by the potential of the connection point of the resistors R1 and R2, and when the transistor TR41 is turned on, the resistor R3 ′ is connected in parallel with the resistor RFA, which will be described later. Thus, the threshold for full charge detection is substantially switched to the threshold for overdischarge detection.

That is, when the transistor TR5 is turned on, the transistor TR4 is passed through the reverse current cut-off diode D '.
1 is turned on, and the resistor R3 ′ is added in parallel with the resistor RFA in the resistor voltage divider circuit including the resistors RFA and RFB. As a result, the voltage division of the cell voltage output by the resistance voltage dividing circuit including the resistors RFA and RFB becomes large. This is equivalent to that the reference voltage output by the reference voltage circuit including the resistor RUF and the reference voltage source VRF becomes relatively small. Therefore, when the transistor TR41 is turned on, this reference voltage is changed from the threshold voltage for full charge determination to the threshold voltage for overdischarge determination.

The threshold value switching control circuit 401 includes resistors R0 'and R0 "which are connected in series with each other and constitute a resistor R0 for flowing a current i0 as a whole, and transistors TR4 and TR5.
And a pulse thinning circuit X2 which is substantially a 1/2 frequency dividing circuit
Consists of.

The battery controller 2 periodically turns on the sampling switch 20 for a predetermined time including a sampling period for sampling the total current ΣI every time T. When the sampling switch 20 is turned on, the line L1
Through the resistors R0 ', R0 ", the output line L, and the sampling switch 20, the voltage conversion circuit 21 absorbs the current i0, so that the transistor TR4 is turned on and the input terminal IN of the pulse thinning circuit X2 is turned on / off in the same manner as the switch 20 is turned on / off. The pulse signal of the timing is input.

As shown in FIG. 10, the inside of the pulse thinning circuit X2 is composed of a current buffer circuit 200, a D flip-flop circuit 201, and an AND gate 202, which thins an input pulse every time. Output (divided by 1/2). When the output of the pulse thinning circuit X2 becomes high level, the transistor TR5 is turned on, the transistor TR41 of each comparison unit circuit 321 is turned on, and the voltage division of the cell voltage applied to the non-inverting input terminal of the comparator 306 changes, This has the same effect as changing the threshold value relatively.

That is, when the output voltage of the pulse thinning circuit X2 does not turn on the transistor TR5, the substantial threshold becomes the full charge threshold voltage VF, and when it turns on, the substantial threshold is over-discharged. Set the resistance values of resistors RFA, RFB, and R3 'to the threshold voltage VL. As a result, the presence or absence of the full-charge determination result (current i3) is detected at the odd number of times when the sampling switch 20 is turned off, and the presence or absence of the over-discharge determination result (current i1) at the even number of times when the sampling switch 20 is turned on. To be detected. After all, in this embodiment, the presence / absence of the full-charge determination result (current i3) and the presence / absence of the over-discharge determination result (current i1) are sampled by the microcomputer 1 for each sampling of the sampling switch 20 in time sequence.
00 will be read. If the sampling interval of the sampling switch 20 is shortened, the full-charge determination result and the over-discharge determination result can be read substantially at substantially the same time, so there is no practical problem, and the full-charge and over-discharge conditions do not occur. Can be integrated into one,
The circuit configuration can be simplified. (Modification) In the above embodiment, the sampling switch 2
By periodically operating 0, the threshold value was switched periodically, but in addition, in the full charge capacity measuring operation period (t0 to t8) shown in FIG. And the selection of the overdischarge determination threshold value may be switched. Preferably, in FIG. 8, the time t at which it is detected that all the cells are equal to or higher than the full charge voltage.
It is preferable that the full-charge determination is performed up to 5, and then the over-discharge determination is performed until time t8 when the discharge is completed.

In the above embodiment, the number of series cells in each cell group need not be limited to four. However, due to the problem of withstand voltage of the elements used in the cell overcharge / discharge detection device, it is considered appropriate to configure the cells in series of 4 to 6 in the case of a lithium battery having an average cell voltage of 3.6V.

In addition to equalizing to full charge and discharging to measure the capacity, equalization is performed on the side of empty charge (SOC = 0%) and then at least one cell is charged until it is overcharged,
The current integrated value during that time may be used as the full charge capacity. In this case, the complete discharge threshold value VE is set to a value slightly higher than the overdischarge threshold value VL, an empty charge detection circuit is provided in each cell, and the output thereof is ORed to determine that the voltages of all cells are VL and VE. It is preferable to determine whether or not there is an interval. To calculate the capacity in this case, it is necessary to multiply the charge capacity by the charge / discharge efficiency. Further, as in the second embodiment, the overcharge detection circuit having the threshold value switching circuit can be substituted for the empty charge detection circuit.

In addition, it is detected that all cells are present in a predetermined voltage range corresponding to two intermediate SOC ranges without being fully charged or completely discharged, and then discharged or charged to a predetermined voltage from there. Alternatively, the full capacity may be estimated by measuring the partial capacity and proportionally converting the partial capacity. In this case, a detection circuit set to an upper threshold voltage corresponding to the upper limit of the intermediate SOC range and a lower threshold voltage corresponding to the lower limit of the intermediate SOC range is prepared, and the former is ORed. Then, the latter is collectively determined by AND logic. Then, as in the second embodiment,
The R logics and the AND logics may be integrated in a threshold switching manner.

The full charge detection signal, the overcharge detection signal, and the overdischarge detection signal can be separately output to the battery controller 2.

Further, the ON / OFF level may be transmitted via the photocoupler without converting the transmission signal into current.

As a threshold value switching method in the second embodiment, the generated voltage of the reference voltage source may be divided and switched instead of changing the cell voltage division ratio. In addition, including the embodiment of FIG. 3, one reference voltage source is shared for each cell, and the reference voltage output from the reference voltage source is divided to overcharge threshold voltage VU and overdischarge threshold voltage. The voltage VL and the full-charge threshold voltage VF may be created and supplied to the comparator.

In the second embodiment, the overcharge detection circuit and the overcharge detection circuit may be shared by the comparators, instead of switching the full charge detection circuit and the overdischarge detection circuit in common. However, in this case, it is necessary to distribute the output of the overcharge / full charge common comparator to both the AND circuit and the OR circuit. Furthermore, the three comparators for determining overcharge, full charge, and overdischarge may be integrated into one, and the threshold may be of a three-state switching type.

A control signal for switching the threshold value may be transmitted using a signal line different from the output line L. In the second embodiment, the relationship between the logic of the switching signal and the threshold value may be reversed (over discharge when L, full charge when H). However, when the cell voltage exceeds the threshold value, basically O
Since the operation is N-operation and the operating current is large, the current consumption from the cell is large. Therefore, if the threshold value is higher when the switching signal is L (for full charge determination), the operating current flows for a shorter time, so that the current consumption can be suppressed. In particular, when the vehicle is stopped (the ignition switch is OFF), it is not necessary to detect overcharging and discharging, and therefore the sampling switch 20 is kept open so that the threshold value is automatically set to the full charge side. Therefore, the current consumption can be suppressed.

The logic of overcharge, full charge, and overcharge detection of each cell (output of each comparator) does not necessarily have to follow those shown in this embodiment. For example, normally, at H level, overcharge or overdischarge detection is performed. It may be set to the L level at times. However, since the consumption current from the cell increases at the H level due to the flow of the operating current, it is preferable to use the logic at the L level when the voltage is below the threshold value.

It goes without saying that the present invention may be applied to a device other than HEV or EV which uses a multi-series assembled battery as a power source.

The target battery is not limited to a lithium secondary battery, but may be any other unit battery such as a lead battery, a nickel-based battery, or another secondary battery cell, or a cell module in which a plurality of cells are arranged in parallel. The present invention is applicable.

[0114]

Third Embodiment Another embodiment will be described below with reference to the flowchart shown in FIG.

In the above-described first and second embodiments, the full charge capacity measuring process can be performed while the vehicle is traveling while the engine bears the traveling power. At this time, the precharge power of the battery pack 1 for the full charge capacity measurement process is supplied from the engine, and the subsequent discharge energy is released to the engine or the wheels.

However, in Embodiments 1 and 2 described above, the charging current value and the discharging current value during the full charge capacity measurement process are determined by the battery controller 2 side regardless of the driving situation. In order to do so, it is naturally possible to add current control suitable for vehicle running. An example thereof is shown as a flowchart in FIG. The discharge current of the battery pack 1 for measuring the full charge capacity gradually increases the discharge current value ID when the discharge current value (average value) IR suitable for running the vehicle is much larger than the current discharge current value ID. And, in the opposite case, it goes down gently. Of course, this discharge current
The change of ID should be made within a predetermined range.

In addition, the battery pack 1 is inevitable when the vehicle is running.
In a situation requiring rapid charging / discharging, the preliminary charging for full charge capacity measurement and the subsequent discharging may be interrupted once, for example, sudden braking or rapid acceleration.

The above-described control for measuring the full charge capacity is performed after monitoring the traveling condition in advance and automatically or manually confirming the traveling condition suitable for this control such as during highway traveling. Good.

[Brief description of drawings]

FIG. 1 is an overall circuit diagram of an on-vehicle assembled battery control device according to a first embodiment.

FIG. 2 is a circuit diagram showing an overcharge detection circuit.

FIG. 3 is a circuit diagram showing an overdischarge detection circuit.

FIG. 4 is a circuit diagram showing a battery controller.

FIG. 5 is a circuit diagram showing a simple equalization circuit.

FIG. 6 is a circuit diagram showing a full charge detection circuit.

FIG. 7 is a flowchart showing a full charge capacity measuring operation in the first embodiment.

FIG. 8 is a timing chart showing a full charge capacity measurement operation in the first embodiment.

FIG. 9 is a circuit diagram showing a circuit that performs full charge detection and overdischarge detection according to a second embodiment.

10 is a circuit diagram showing the pulse thinning circuit of FIG.

FIG. 11 is a flowchart showing discharge current control according to the third embodiment.

[Explanation of symbols]

11-1N Cell groups 31-3N Simple cell overcharge / discharge detection device (voltage detection unit,
Battery management part) 2 Battery controller (current integration part, battery management part) CCC Overcharge detection circuit (high level determination means, overcharge detection means) CDC Overdischarge detection circuit (low level determination means, overdischarge detection means) CFC Full Charge detection circuit (intermediate level determination means, full charge detection means) CXC Full charge / over discharge detection circuit CEC Simple equalization circuit (cell voltage equalization circuit) 401 Threshold switching control circuit (threshold switching signal generation means) 400 threshold value switching circuit TR1, TR2, TR3 transistor (current modulation means) 20 sampling switch

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01M 10/48 ZHV H01M 10/48 ZHVP F term (reference) 2G016 CA03 CB12 CB22 CB32 CC01 CC04 CC07 CC12 CC23 CC24 CC27 CD01 CD03 CD04 CD09 5G003 AA07 BA03 DA07 EA05 FA06 GC05 5H030 AA03 AA04 AA08 AS08 BB01 BB21 DD20 FF42 FF43 FF44 5H115 PA08 PA11 PG04 PI16 PO17 PU01 PU21 PV09 PV23 QE09 QI04 QN02 SE06 TI01 TUTU16 TI06 TI02 TI05 TI06

Claims (14)

[Claims] 1. A voltage detection unit for detecting the voltage of a large number of cells that are connected in series to each other to form an assembled battery for an automobile, and a current integrating unit for computing an integrated current amount obtained by integrating the charging and discharging currents of the assembled battery. And a battery management unit that manages a battery state of the assembled battery by performing a calculation based on the output signals of the both detection units, the battery management unit including: And a full charge arrival time when all have reached a predetermined full charge voltage, and an empty charge arrival time when at least one of the voltages of each cell before or after the full charge arrival time reaches a predetermined empty charge voltage. Is detected and the integrated current amount between the both time points is set as the full charge capacity. 2. A voltage detection unit for detecting the voltage of a large number of cells that are connected in series to each other to form an assembled battery for an automobile, and a current integrating unit for computing an integrated current amount obtained by integrating the charging and discharging currents of the assembled battery. And a battery management unit that manages a battery state of the assembled battery by performing an operation based on the output signals of the both detection units, the battery management unit is configured such that at least one of the voltages of the cells is predetermined. High level determination means for determining that the charging level is a predetermined high level when the voltage is equal to or higher than the high voltage value, and at least one of the voltages of the cells is less than a predetermined low voltage value lower than the high voltage value. Low level determining means for determining that the charge level is a predetermined low level when all of the cells have a predetermined full charge capacity detection time point between the high voltage value and the low voltage value. Intermediate high voltage value for If the charge level is determined to be a predetermined intermediate high level, or if all of the voltages of each cell are a predetermined full charge capacity detection value between the intermediate high voltage value and the low voltage value. An intermediate level determination unit that determines the charge level to be a predetermined intermediate low level when it becomes less than the intermediate low voltage value for determination, and the charge level is equal to or higher than the intermediate high level and is less than the discharge start time from the high level. Until the low level or the intermediate low level is reached by starting discharging, or the charge is started at a charging start point of the low level or higher at the intermediate low level or lower to reach the high level or the intermediate high level. Up to a full charge capacity calculation means for calculating the full charge capacity based on the integrated current value obtained by integrating the current. 3. The on-vehicle assembled battery control device according to claim 2, wherein the battery management unit is connected in parallel with each of the cells and bypasses a current of the cell, and a current bypass circuit between the cells. A bypass voltage control circuit for controlling the voltage variation between the cells within a predetermined range by adjusting the bypass current of the current bypass circuit according to the voltage variation, and a cell voltage equalizing circuit including: In-vehicle assembled battery control device. 4. The in-vehicle assembled battery control device according to claim 2, wherein the battery management unit sets the predetermined high voltage value, which is a determination reference value of the high level determination unit, to an allowable upper limit voltage value of the cell. In addition, when the high level determination means determines that the high level, the in-vehicle assembled battery control device is instructed to reduce or interrupt the charging current. 5. The on-vehicle assembled battery control device according to claim 2, wherein the battery management unit sets the predetermined low voltage value, which is a determination reference value of the low level determination unit, to an allowable lower limit voltage value of the cell. In addition, the in-vehicle assembled battery control device is configured to instruct the reduction or interruption of the discharge current when the low level determination means determines that the low level. 6. The on-vehicle assembled battery control device according to claim 2, wherein each of the cells comprises a lithium secondary battery having a positive electrode and a negative electrode capable of inserting and extracting lithium ions. The determination means comprises overcharge detection means for detecting overcharge of each cell, and the low level determination means comprises overdischarge detection means for detecting overdischarge of each cell. Control device. 7. The in-vehicle assembled battery control device according to claim 2, wherein the high level determination means and the intermediate low level determination means determine the voltage of each cell and a predetermined reference value for each cell. A plurality of comparing units, a logical sum calculating unit that outputs a logical signal corresponding to the logical sum of the outputs of the comparing units, and the reference value of each comparing unit that is the first for the high level determination. An in-vehicle assembled battery control device comprising: a threshold value switching unit that switches between a threshold value and a second threshold value for determining the intermediate low level. 8. The on-vehicle assembled battery control device according to claim 2, wherein the low level determination unit and the intermediate high level determination unit determine the voltage of each cell and a predetermined reference value for each cell. A plurality of comparison units, a logical product operation unit that outputs a logical signal corresponding to a logical product of the outputs of the respective comparison units, and the reference value of each of the comparison units, the third value for the low level determination. An in-vehicle assembled battery control device comprising: a threshold value switching unit that switches between a threshold value and a fourth threshold value for determining the intermediate high level. 9. The on-vehicle assembled battery control device according to claim 2, wherein the battery management unit changes the output current amount output to a single output line by the output of each of the determination means. An in-vehicle assembled battery control device having a modulation means. 10. The on-vehicle assembled battery control device according to claim 7, 8 or 9, wherein the battery management unit periodically samples the output current of the output line to a signal processing circuit in a subsequent stage. A sampling switch for outputting, and threshold value switching signal generating means for instructing threshold value switching of the threshold value switching section based on a change in output current of the current modulating means due to opening and closing of the sampling switch. An in-vehicle assembled battery control device characterized by: 11. The on-vehicle assembled battery control device according to claim 2, wherein the battery management unit sets the state of each cell to the high level above the intermediate high level when detecting a full charge capacity. Charge command operation to charge up to less than, a cutoff command operation to cut off the charge current when one of the cells becomes the high voltage value, after a lapse of a predetermined time from the cutoff, all cells are the intermediate high voltage If the value is equal to or more than the value and less than the high voltage value, a discharge command operation for permitting discharge for current integration for obtaining the full charge capacity thereafter is executed. 12. The on-vehicle assembled battery control device according to claim 11, wherein the battery management unit, when detecting a full charge capacity, sets the cell voltage to the high voltage between the charge command operation and the cutoff command operation. An in-vehicle assembled battery control device, which executes a reduction command operation for reducing the charging current each time the value is reached. 13. The on-vehicle assembled battery control device according to claim 11, wherein the battery management unit detects at least one cell is less than the intermediate high voltage value after a predetermined time has elapsed after the cutoff when detecting the full charge capacity. If it is reduced to 0, a recharge command operation for recharging at a predetermined current value is executed. 14. The in-vehicle assembled battery control device according to any one of claims 2 to 5, wherein the assembled battery for a vehicle stores electric power that assists or regenerates power of a hybrid electric vehicle, and the battery management unit includes: An in-vehicle assembled battery control device for increasing or decreasing a discharge current or a charging current at the time of integrating the full charge capacity according to a required value of an output or a regenerative current while the hybrid electric vehicle is running.